It is a characteristic of envelope-filling machines of this type that some of the assembly parts require a continuous drive or a partially continuous drive which is achieved by controlled clutch actuation, while another part of the assembly parts of a machine of this type require an intermittent drive.
An enclosure-collating path having endless, circulating conveyor belts or chains which are oriented in the longitudinal direction and define enclosure compartments along their upper run between conveying fingers is driven intermittently in that region in which the enclosure-collating path runs past enclosure-feeding stations when the latter are driven synchronously, or is provided with a continuous drive if the enclosure-feeding stations can insert enclosures into the moving enclosure-collating path. In every case, however, an end section of the enclosure-collating path has to move the enclosure conveying compartments forwards intermittently, as a push-in station which is provided at the end of the enclosure-collating path, performs a working stroke in the transverse direction and is intended for inserting a set of enclosures into an envelope requires intermittent conveying of the sets of enclosures. The intermittently driven end section of the enclosure-collating path, which end section adjoins a continuously driven section of the enclosure-collating path, accepts the continuously conveyed sets of enclosures on account of a greater conveying speed and conveys them in front of the push-in station, whose push-in apparatus works synchronously but is actuated by a continuous drive, for example via a crank mechanism. The same applies to gripper arrangements which are provided in the enclosure-feeding stations and are driven synchronously via a common pivoting shaft running in the longitudinal direction of the envelope-filling machine but are in turn actuated from a continuously circulating drive shaft, for example via a crank mechanism.
The envelopes can be conveyed on an envelope-filling table which lies next to and parallel to the enclosure-collating path, initially by means of continuously actuated conveying means, for example conveyor belts moved with their upper run approximately at the level of the envelope-filling table, as far as the push-in station. If an envelope has been filled with a set of enclosures, a synchronously driven conveyor chain then grips the filled envelope or item of mail, pulls the item of mail out of the region in front of the push-in station, pulls it through an envelope-closing path and finally feeds it to an apparatus for further conveying or pulls it into an envelope-turning station which turns over the filled envelope so that its address side or envelope window side lies on top and subsequently feeds it to an apparatus for further conveying. The turning station is driven synchronously, which happens by coupling it to a continuous drive in a time-controlled manner.
The drive system of the known mail-processing machines or envelope-filling machines comprises, below the level of the enclosure-collating path, the base plate of the push-in station and the surface of the envelope-filling table, an electric drive motor in a framework and a step-down gear mechanism attached to the said drive motor, which is, however, not shown in the above-mentioned DE 198 30 337 C1. Furthermore, the drive system of the known machines comprises a bevel gear mechanism and a step-by-step motion linkage which is coupled to the said bevel gear mechanism. This drive system thus provides output shafts which cause shafts which extend in the longitudinal direction of the machine, that is to say parallel to the longitudinal orientation of the enclosure-collating path, to rotate continuously, these shafts making the actuation movements possible which proceed in a transverse direction with respect to the longitudinal direction of the machine, via crank mechanisms or eccentric drives. Furthermore, the drive system provides continuously rotating output shafts which are oriented in the transverse direction and make it possible to drive shafts which extend in the transverse direction and are coupled to enclosure-conveying means or to envelope-conveying means, as long as the latter are to be driven continuously, and furthermore provides output shafts of the step-by-step motion linkage which are coupled to shafts which require intermittent enclosure conveying or intermittent envelope conveying.
It has been shown then that, in the known mail-processing machines or envelope-filling machines of the above-discussed type, the arrangement of the various drive members, transmission shafts and drive shafts below the level of the enclosure-collating path, the envelope-filling table and, in particular, below the enclosure-feeding stations, takes up a considerable amount of space, is very complicated and prevents defined sensor devices from being attached below the enclosure-feeding stations.